I just completed a pond last fall, just shy of a full acre with a maximum depth of 14 feet. It was built in the middle of a wooded area, in a natural run. It required a dam and extensive excavation, Many trees had to be removed, and after we reached 6 feet in depth we hit "gumbo" clay which caused all kinds of problems such as: what do you do with it, where do you put it, and how? Of course the pond does not leak, and I had plenty of material for the dam. Total cost was about $5000.00 I strongly recommend paying the land contractor by the hour as opposed by the quote. Even in my case with the clay, I came out ahead. My contractor had very little experience with ponds, but I was on site the entire time. I've read and studied everything I can, including POND BOSS MAGAZINE and I am quite pleased with the outcome as are my pond buddies. Do your homework, be on site. You're paying for it afterall.